1998 ISUZU TROOPER headlight bulb

WIRING SYSTEM 8DÐ139
1Ð4. Headlight Low-Beam On The Left (Or Right) Side Inoperative
·IS THE HEADLIGHT BULB ON THE
LEFT (OR RIGHT) SIDE NORMAL?
YES
·IS THE FUSE F–4 (15A) (OR F–5 (15A))
NORMAL?
YES
REPLACE THE BULB
NO
·DISCONNECT THE DIMMER·PASSING SW CONNECTOR
·WITH THE SWITCH AT THE LOW–BEAM POSITION, IS THERE
CONTINUITY BETWEEN 13 B–12 AND 16 B–12 ?
YES
REPLACE THE FUSE
NO
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 3 C–21 AND F–4
(15A) (OR 3 C–32 AND F–5 (15A))
NO
REPAIR OR REPLACE THE DIMMER·PASSING SWREPAIR A POOR CONNECTION AT THE CONNECTORS OR AN
OPEN CIRCUIT BETWEEN 13 B–12 AND 1 C–21 (OR 13 B–12
AND 1 C–32 )
·IS THE CONTINUITY BETWEEN
3 C–21 AND F–4 (15A) (OR 3 C–32
AND F–5 (15A)) NORMAL?
NOYES

8DÐ140 WIRING SYSTEM
1Ð5. Both Headlights In High-Beam Inoperative
·DISCONNECT THE DIMMER•
PASSING SW CONNECTOR (COMBINATION SW)
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN
15 B-12 AND 16 H-16REPAIR OR REPLACE THE DIMMER•
PASSING SW
NO
·WITH THE SWITCH AT HIGH-BEAM, IS THERE
CONTINUITY BETWEEN THE SWITCH CONNECTOR TERMINALS
15 B-12 AND 16 B-12 ?
1Ð6. Headlight High-Beam On The Left (Or Right) Side Inoperative
·IS THE HEADLIGHT BULB ON THE
LEFT (OR RIGHT) SIDE NORMAL?
YES
·IS THE FUSE F–4 (15A) (OR F–5 (15A))
NORMAL?
YES
REPLACE THE BULB
NO
·DISCONNECT THE DIMMER·PASSING SW CONNECTOR
·WITH THE SWITCH AT THE HIGH–BEAM POSITION, IS THERE
CONTINUITY BETWEEN 15 B–12 AND 16 B–12 ?
YES
REPLACE THE FUSE
NO
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 3 C–21 AND F–4
(15A) (OR 3 C–32 AND F–5 (15A))
NO
REPAIR OR REPLACE THE DIMMER·PASSING SWREPAIR A POOR CONNECTION AT THE CONNECTORS OR AN
OPEN CIRCUIT BETWEEN 15 B–12 AND 2 C–21 (OR 15 B–12
AND 2 C–32 )
·IS THE CONTINUITY BETWEEN
3 C–21 AND F–4 (15A) (OR 3 C–32
AND F–5 (15A)) NORMAL?
NOYES

8DÐ144 WIRING SYSTEM
2-2. Headlight On The Left (Or Right) Side Inoperative
·IS THE HEADLIGHT BULB ON THE LEFT (OR RIGHT) SIDE
NORMAL?
YES
REPLACE THE BULB
NO
·IS 7 C-39 (OR 5 C-39 ) GROUNDED SECURELY? (RH)
IS 4 C-39 (OR 7 C-16 ) GROUNDED SECURELY? (LH)
YESNO
GROUND IT SECURELY
REPAIR AN OPEN CIRCUIT BETWEEN
3 C-32 AND 7 C-39 (OR 5 C-39 ) (RH)
3 C-21 AND 4 C-39 (OR 7 C-16 ) (LH)
·IS THE DIMMER RELAY NORMAL?
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN 2 X-3 AND FUSE F-6 (10A)
NO
REPLACE THE RELAY
2-3. Both Headlights In Low-Beam Inoperative

WIRING SYSTEM 8DÐ145
2-4. Headlight Low-Beam On The Left (Or Right) Side Inoperative
2-5. Both Headlights In High-Beam Inoperative
·IS THE HEADLIGHT BULB NORMAL?
YESNO
REPLACE THE BULB·IS THE FUSE F-6 (10A) (OR F-7 (10A)) NORMAL?
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN FUSE F-6 (10A) AND 1 C-21
(OR FUSE F-7 (10A) AND 1 C-32 )
NO
REPLACE THE FUSE
·IS THE DIMMER RELAY NORMAL?
YESNO
REPLACE THE RELAY·
·DISCONNECT THE DIMMER·PASING SW CONNECTOR
IS THERE ANY CONTINUITY BETWEEN THE SWITCH SIDE
CONNECTOR 15 B-12 AND 16 B-12 WHEN THE
SWITCH IS AT HIGH-BEAM POSITION?
YESNO
REPAIR OR REPLACE THE SWITCH·IS THE BATTERY VOLTAGE APPLIED BETWEEN THE
HARNESS SIDE CONNECTOR 15 B-12 AND GROUND
WHEN THE SWITCH IS AT HIGH-BEAM POSITION?
YESNO
REPAIR A POOR CONNECTION AT THE CONNEC-
TORS OR AN OPEN CIRCUIT BETWEEN 5 X-3
AND 15 B-12REPAIR A POOR CONNECTION AT THE CONNECTOR OR AN
OPEN CIRCUIT BETWEEN 3 X-3 AND FUSE F-4 (10A)

8DÐ146 WIRING SYSTEM
2-6. Headlight High-Beam On The Left (Or Right) Side Inoperative
2-7. Headlight Beam Does Not Change
·IS THE CONTINUITY IN THE DIMMER·PASSING
SW NORMAL ?
YES
REPAIR OR REPLACE THE SWITCH
NO
·IS B-19 GROUNDED SECURELY?
YESNO
GROUND IT SECURELY
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN 5 X-3 AND 15 B-12
·IS THE DIMMER RELAY NORMAL?
YESNO
REPAIR AN OPEN CIRCUIT BETWEEN 16 B-12 AND
B-19
REPLACE THE RELAY·IS THERE CONTINUITY BETWEEN 16 B-12 AND
B-19 ?
YESNO
·IS THE HEADLIGHT BULB NORMAL?
YESNO
REPLACE THE BULB·IS THE FUSE F-4 (10A) (OR F-5 (10A)) NORMAL?
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN
(LH) FUSE F-4 (10A) AND 2 C-21
(RH) FUSE F-5 (10A) AND 2 C-32
NO
REPLACE THE FUSE

WIRING SYSTEM 8DÐ399
Diagnosis
Diagnosis Procedure
1. Check to see if the battery voltage is normal.
2. Check to see if the fuse is normal.
3. Replace the antiÐtheft & keyless entry control unit with one reserved for test. If a trouble recurs even after replacing
the control unit, find out the cause of the trouble by referring to ÒSystem check procedureÓ and the following list.
ITEM MALFUNCTION POSSIBLE CAUSE DETECTING METHOD REMARKS
ANTIÐTHEFT
indicator light
does not flash
ANTIÐTHEFT
indicator light
does not turn off.
(Steadily on)
When door is
opened by pulling
up locking knob,
alarm does not
operate
Alarm does not
stop. Indicator light
does not change
to fully ON
condition, or does
not come on at
all.Burnt out indicator
light bulb possible.
Refer to ÒConnector
check tableÓ in this
system.
Refer to ÒConnector
check tableÓ in this
system.
Refer to ÒConnector
check tableÓ in this
system.
Refer to ÒConnector
check tableÓ in this
system.
Refer to ÒConnector
check tableÓ in this
system.
Refer to ÒConnector
check tableÓ in this
system. Defective contact of door switch,
or open circuit in door switch
wiring.
Short circuit in the detect switch.
Engine hood, doors and tailgate
are not fully closed and locked.
Defective door switch, or short
circuit in switch wiring.
Defective tamper switch, or short
circuit in wiring.
Defective lock switch, or short
circuit in wiring.
Defective engine hood switch, or
short circuit in wiring.
Defective tailgate switch, or short
circuit in wiring.
Defective control unit.
Poor contact of lock switch, or
open circuit in wiring.
Broken wire in wiring to headlight
and horn, or a blown fuse.
Defective contact of detect
switch, or damaged switch wiring.With door open, dome light and
courtesy light do not come on.
Check the control unit connector.
Check to see if doors are closed
and locked.
Dome light and courtesy light
remain lit on after closing doors.
Check the control unit connector.
Check the control unit connector.
Check the control unit connector.
Luggage room light remains lit
after closing tailgate.
Check alarm operation (See No.
46 of ÒSystem check procedureÓ),
possible cause is a poor contact
of lock switch of an open circuit in
wiring.
Check to see if headlights go out.
Check the control unit connector.
Check the control unit connector. A
C
D
E B